Plaster-cast-cutting device



Feb. 25, 1930. H. v. PARKER PLASTER CAST CUTTING DEVICE Filed Aug. 15, 1929 IN VEN TOR.

I/aze) Vzrgnia Parker Patented Feb. 25, 1930 UNITED STATES PATENT OFFICE I'LASTER-CAST-CUTTING DEVICE Application filed August 15, 1929. Serial No. 386,181.

This invention relates to a power driven cutter for the purpose of cutting plastic casts, and the removal thereof from any part of the human body or from animals.

One object of this invention is to provide a device of this character which is new, novel and practical to use.

Another objectis to provide a device which will first cut the outer plaster cast so that the cast and bandages may be readily removed from the body on which they have been placed. 7

Another object is to provide a device of the class described, which is safe to use and operate and which will do its work without danger of cutting or mutilating the flesh over which it is working.

Another object is to provide a device of the class described, which is compact, small in size, durable, easy to replace parts, speedy in its operation and efficient in doing the work for which it is intended.

The usual method for removing plaster casts is to cut the cast away with a knife. This operation is slow and tedious and nerve racking for the patient as well as hard, tiresome work for the doctor.

With all these and other objects in view, as will be more fully explained as this description progresses, the invention consists in the construction, combination of parts and novel features, pointed out in the claims hereto appended and illustrated in the drawings.

Referring to the drawings: Fig. 1 is a side View of the invention, partly in section for convenience of illustration.

Fig. 2 is a bottom View of the device.

Fig. 3 is a top view of the device.

Fig. 4 is an enlarged detail view taken along line IV-IV in Fig. 1.

Fig. 5 is a sectional view of the device, taken along line V--V in Fig. 1.

Fig. 6 is a bottom plan view of the knife operating mechanism, as taken along the line VI-VI in Fig. 7, looking in the direction of the arrows.

Fig. 7 is a sectional view taken along the line VII-VII in Fig. 6.

Fig. 8 is a detail View, illustrating one of numerous types of cutters which may be employed in this device.

Fig. 9 is a plan View of Fig. 8.

Like characters of reference indicate like parts'in all the figures in which a practical embodiment of the invention is illustrated.

In the drawings, at 10 is shown a housing enclosing an electric motor, the drive shaft of which is shown at '11, to the housing 10 is rigidly attached ahandle 12, through which pass the electric feed wires 13, and in which is embodied an electric switch, the operating handle of which is shown at 14. The housing 1-0 is rigidly attached to a blower housing 15, by means of screws 16. At 17 is an open circular plate, secured to, and forming a base for the blower housing 15 and having cross members 18, integral with the plate, and rigidly supporting an integral gear housing and bearing portion 19. Within the housing 15 is a circular plate 20, having integral fins 21 and a hub portion 22, which forms the rotary blower member, said member being mounted on and rigidly aflixed to the motor shaft 11 by means of a set screw as shown. Aiiixed on the lower end of shaft 11 is a small cog wheel 23, in mesh with a larger cog wheel 24, which is integral with a cylindrical cutter member 25 and revolvably mounted on a shaft 26, said shaft 26 being rigidly fixed in the member 19. The cylindrical member 25 is provided with spiral cutter teeth 27. The outer end of the cylindrical member 25, is provided with a circular groove 28, in the base thereof, said groove being positioned eccentric to the central axis of the cylinder 25. At 29'is shown a slotted shoe held rigid'to the shaft 26 by means of a screw 30, passing the base element '31 of the slotted shoe 29 and entering a hole 32 in the shaft 26. Directly beneath the cylinder 25 is a forked slide member 33, 'having an extended shank 34:. This slide member 33 is located in a slot 33 in the shoe member 29 and between the cylinder 25 and the lowerrelement 31 of said shoe 29. This slide member 33 is provided with a pin 35 engaging within the groove 28.' The upper face of the extension 34 is provided with teeth meshing with teeth 36' on the under rear portion of a' knife member 37, said knife being pivoted I at 38 to parts 29---29 of the shoe member 22. The front portion of shoe member 29 s scooped or plow shaped as shown at 29 and 1s slotted at 33 as Within a guide which the knife 27 oscillates up and-down as indicated by the arrow A, in Fig. 7.

Various types of cylindrical cutters may be employed to best suit the fancy of the oper-. o ator, or the kind of material to be cut. These cylinders may be provided with spiral cutters as shown in Fig. 1, or as shown in Figs. 8 and 9, thecylinder may be studded wlth cutter teeth 40, or any other type of tooth, or cutter which would be applicable to thls device. The operation of this device is as follows: To start the machine, the switch handle 14 is pulled rearwardly, this causes the switch to complete an electric circuit, thereby causing the motor to operate, thus rotating the cogwheel 23. The gear 23 rotates the gear 24 and cutter cylinder 25. The pin 35 on the member 33 in the-eccentric groove 28, and 25 during this rotary motion of the cylinder 25,

the composite member 3334 is driven forwardly and rearwardly in a sliding movement. By reason of the rack and gear mechanism, on the member 34 and the knife 37, 80 the knife 37 is caused to oscillate up and down on the pin 38 for cutting purposes. Now that the-machine is in motion, the shoe 29 is placed on the flesh 41 and slipped be tween the flesh and the bandage 42 and the plaster cast 43, and pushed forward, or so that the knife 37 splits the cotton and bandage under the plaster cast and the rotary cutter cuts away the plaster cast, the cuttings of which travel upwardly and through the open portion of the plate 17 thence outwardly through the tube 44, to a suitable place of deposit. The said dust and cuttings travel this course, by reason of a strong draft of air protion as a rack bar; and a knife element, pivotally mounted within said slotted shoe, having teeth engaging said rack.

2. In a device as described in claim 1, a blower housing, an air intake, a power fan and shaft rotatable within said housing, said shaft carrying a gear enmesh with a gear on the cutter and for driving said cutter and knife, and an exhaust tube for said blower.

3. In a device as described in claim 1, a motor housing having a handle passing feed wiresof an electric circuit, an electric switch, an electric motor within the housing having a shaft; a blower housing, rigid to the motor housing, a fan with the blower housing and a gear rigid to the motor shaft, an air intake and an exhaust for said blower; and a'second gear rigid to the cylindrical cutter enmesh with the gear on the motor shaft and for driving said cutter and knife during motor operation.

In testimony whereof she affixes her signature.

HAZEL VIRGINIA PARKER.

vided by the blower 21, as heretofore de- 45 scribed.

Due to the cylindrical shape of the cutter, it is obvious that an irregular shaped cut may be made in a cast. This is of decided advantage in cutting or splitting a cast of a curved shape, such for instance as at the bend of the elbow, onat theknee joint and the like.

- Such modifications may be employed, as lie within the scope of the appended claims.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent is: I

1. In a device of the class described, a slotted shoe and a stud rigid thereto; a power operable cylindrical cutter rotatable on said stud, a circular slot in the base of said cutter eccentric to the axis thereof; a forked member adapted to slide within said slotted shoe and having a pin engaging said circular slot, the forks of said member passing the base of said stud and having an extended shank por- 

